The aminoglycoside antibiotics are a well recognized, useful class of antibiotics. One of the most recently recognized aminoglycoside antibiotic families has been the fortimicin family of antibiotics. See U.S. Pat. Nos. 3,976,768 and 3,931,400 which disclose fortimicins A and B.
As with other antibiotics, chemical modification of the fortimicin family of antibiotics has provided useful entities which are either intrinsically more active than the parent antibiotics, have activity against resistant strains of organisms or have reduced toxicity.
Heretofore, it has been necessary to produce fortimicin B and chemically modify that parent antibiotic in order to obtain the desired derivative and this has often required reaction involving numerous, complicated steps.
It has now been found that by converting a suitably protected fortimicin B to the bis-carbamate, and cleaving the glycoside bond to obtain fortamine-bis-carbamate, a number of aminoglycoside antibiotics can be readily prepared simply by reacting the protected fortamine with a suitably protected sugar, in the case of the fortimicins, with a suitably protected purpurosamine as taught in commonly assigned, co-pending U.S. Ser. No. 079,131 filed of even date with the present application.